virtual function in destructor

[Steffen Jahn]

Hi,

another strange behavior is the handling of virtual 
functions in desctructors. Please take a look at the
examples below.

The first example causes no problems.

struct A
{
  ~A(void) { f() ; }
  virtual void f(void) = 0 ;
} ;

struct B : public A
{
  virtual void f(void) { }
} ;

void main() { B b ; }

The second example, which is the same as the first one,
does only define the destructor outside the class scope.

struct A
{
  ~A(void) ;
  virtual void f(void) = 0 ;
} ;

A::~A(void) { f() ; }

struct B : public A
{
  virtual void f(void) { }
} ;

void main() { B b ; }

And g++ (linker) complains:

/usr/bin/ld:
Unresolved:
A::f(void)
collect2: ld returned 1 exit status

As a work around, you have to use virtual function
only in the class scope (inline) in destructors.

regards
Steffen

btw:
% g++ -v
Reading specs from .../alphaev56-dec-osf4.0d/2.95.3/specs
gcc version 2.95.3 20010315 (release)

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